27. Resistors & DC Circuits
Resistors and Ohm's Law
7PRACTICE PROBLEM
You are working on a circuit that requires an ammeter with a full-scale reading of 75.0 mA. However, the only ammeter available in the storeroom has a range from 0 μA to a full-scale reading of 300.0 μA. The resistance of the ammeter is measured to be 60.0 Ω. To achieve the desired 75.0 mA reading capacity, you consider adding a resistor in parallel to the ammeter. Calculate the effective resistance of the modified ammeter (which is a combination of the ammeter and the parallel resistor).
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You are working on a circuit that requires an ammeter with a full-scale reading of 75.0 mA. However, the only ammeter available in the storeroom has a range from 0 μA to a full-scale reading of 300.0 μA. The resistance of the ammeter is measured to be 60.0 Ω. To achieve the desired 75.0 mA reading capacity, you consider adding a resistor in parallel to the ammeter. Calculate the effective resistance of the modified ammeter (which is a combination of the ammeter and the parallel resistor).